The research evaluated the marker of oxidative stress and antioxidants status in Gestational diabetic women (GD) in Saladdin governorate,through measuring the end-product of lipid peroxidation ( Malondialdehyde-MDA) and the antioxidants (Reduced glutathione,Vit.C,Total phenols ). The study was carried out on (68) women age (19–40) year, included (25) gestational diabetic , compared with non-pregnants (22) and normal pregnant women (21) with similar age as control group.The study showed that MDA level was significantly increase in the gestational diabetic women compared to non-pregnants and normal pregnant women.While the antioxidants status (Reduced glutathione, Vit.C ,Total phenols) showed a significant decrease in their levels.Moreover, the research also included a study of the effect of women age on the studied biochemical parameters , the results showed significant increase in MDA level in (25-40)year age group compared to (19-24) year group of gestational diabetic women , non-pregnants and normal pregnant women.While the antioxidants status (Reduced glutathione, Vit.C , Total phenols) showed a significant decrease in their levels in (25-40) year age group compared to (19-24) year group of gestational diabetic women , non-pregnants and normal pregnant women